The UCD ADC has maintained a successful data management program as part of the Clinical Core since it was initially funded in 1991, but Center needs have evolved requiring a formal biostatistics component to the program for further advancement. The need for additional statistical input is driven by the complex nature of the multi-dimensional and longitudinal relationships the UCD ADC will be examining in addressing the theme of how the expression of Alzheimer's disease is modified by ethnicity and cerebrovascular disease. The Core will utilize a number of existing techniques at the ADC, but develop a number of expanded capabilities. Specific Aims for the new Core will be to: 1) continue systematic data collection, entry, and management, 2) provide statistical consultations for investigators with the ADC, and 3) develop new statistical methodology to address research questions of the UCD ADC. The data management structure will use the existing ADC components including a computer assisted entry process using Visual FoxPro, merging of data sets from multiple sources, on line documentation, and a high level of security protection. The database has capabilities for regular reporting to the Executive Committee and NIA and NACC, as well as the ability to generate reports of subject availability and recruitment. Statistical support will be aimed at the analysis of existing data and the generation of power calculations, as well as hypothesis testing. While the ADC data set contains a number of challenges related to its longitudinal nature, the investigators are familiar with many existing techniques to address these problems and well develop new methods of data analysis as part of the mission of the core.